Not sure if KRELL is still in business but their "new" k-300i integrated amp is great. The first 90 watts is in Class A and a total of 150 watts at 8 Ohm. I had the CODA CSIB v1 at the same time and preferred the KRELL.
I have heard the new SimAudio Moon Collection 761/791 combo, and it was really good. A super clean sound like a Benchmark AHB2 amp but warmer. I have not heard the integrated amp in the lineup, but if I were only looking for an integrated amp I would also look at
https://simaudio.com/en/product/641-integrated-amplifier/
BTW - if you only need a single digital source then I would pair your BHK amp with my imersiv D-1 DAC/preamp. It means you would only have 1 source into the DAC. It is a unicorn DAC with respect to the level of detail you hear. With your slightly warm amp it would be a spectacular. You would need to get an attachment from imersiv to hookup the subs.
This is how I am using my good system. Streaming into the DAC via USB and also SACD/CD’s via a transport into the same DAC on SPDIF.
This DAC is sonically compromised if you hook it up to a preamp. Defeats the purpose of buying this DAC.